Mines in San Luis Obispo County, California

San Luis Obispo County, California has 553 mine and mineral deposit locations documented in federal records from the USGS and MSHA. 109 of these are currently active mining operations. The most commonly recorded commodity is chromium, with 149 sites. The table below lists all recorded mines in the county with links to individual site details.

All Mines in San Luis Obispo County

Mine	Commodity	Type	Status	Source
Bianchi Pit	Construction Sand and Gravel	Surface	Active	MSHA
Blue Mountain Minerals Pr Llc	Crushed, Broken Limestone NEC	Surface	Active	MSHA
Navajo Rock & Block	Construction Sand and Gravel	Surface	Active	MSHA
Rocky Canyon Plant	Crushed, Broken Granite	Surface	Active	MSHA
Santa Margarita Aggregates	Construction Sand and Gravel	Surface	Active	MSHA
Warrior 1800/cone Crusher Ft200	Sand, Industrial NEC	Surface	Active	MSHA
Whale Rock Quarry	Crushed, Broken Stone NEC	Surface	Active	MSHA
12th Street Pit	Sand and Gravel, Construction	Surface	Producer	MRDS
3 Bar 5 Ranch Pit	Stone, Dimension	Surface	Producer	MRDS
Arrisa Mine	Gypsum-Anhydrite		Producer	MRDS
Barnaberg Mine	Magnesite		Producer	MRDS
Barneberg Mine	Manganese		Producer	MRDS
Beck Quarry #4	Gypsum-Anhydrite	Surface	Producer	MRDS
Bianchi Quarry	Stone, Crushed/Broken	Surface	Producer	MRDS
Bluebird Mine	Manganese		Producer	MRDS
Branch Pit	Sand and Gravel, Construction	Surface	Producer	MRDS
Buena Vista	Mercury		Producer	MRDS
Cambria Pit	Stone, Crushed/Broken	Surface	Producer	MRDS
Captian Deposit	Chromium		Producer	MRDS
Castro Mine	Chromium		Producer	MRDS
Castro Mine-Trinidad Mine	Chromium		Producer	MRDS
Chorro Mine	Chromium		Producer	MRDS
Chucker #3 Mine	Gypsum-Anhydrite	Surface	Producer	MRDS
Cienaga Mine	Chromium		Producer	MRDS
Cienega Creek Quarry	Stone, Crushed/Broken	Surface	Producer	MRDS
Colonel Deposit	Chromium		Producer	MRDS
Dana Ranch Pit	Sand and Gravel, Construction	Surface	Producer	MRDS
Davis Quarry	Stone, Crushed/Broken	Surface	Producer	MRDS
Dirtman Pit	Sand and Gravel, Construction	Surface	Producer	MRDS
Domechini Pit	Sand and Gravel, Construction	Surface	Producer	MRDS
Eagle Claim	Chromium		Producer	MRDS
El Divisadero	Chromium		Producer	MRDS
El Prinero Mine	Chromium		Producer	MRDS
El Salto Mine	Chromium		Producer	MRDS
Estrella Pit	Sand and Gravel, Construction	Surface	Producer	MRDS
Eucalyptus No 1 Claim	Chromium		Producer	MRDS
Farm Camp Quarry No. 5	Gypsum-Anhydrite	Surface	Producer	MRDS
Fenceline Quarry #8	Gypsum-Anhydrite	Surface	Producer	MRDS
Gambrie Mine	Mercury		Producer	MRDS
Gemstone Nos. 1, 2, & 3	Mercury		Producer	MRDS
Grieb Ranch Quarry	Flagstone	Surface	Producer	MRDS
Guerra Quarry	Stone, Crushed/Broken	Surface	Producer	MRDS
Hearst Ranch - Red Rock Deposit	Manganese		Producer	MRDS
Homeplace Pit	Stone, Crushed/Broken	Surface	Producer	MRDS
Huasna River Pit	Sand and Gravel, Construction	Surface	Producer	MRDS
Jitney Mine	Chromium		Producer	MRDS
Jobe Ranch Mine	Manganese		Producer	MRDS
Johnson Ranch Deposit	Chromium		Producer	MRDS
Kaiser-Santa Margarita Pit	Stone, Crushed/Broken	Surface	Producer	MRDS
Kolrich Pit	Stone, Crushed/Broken	Surface	Producer	MRDS
La Libertad	Mercury		Producer	MRDS
Land Red Rock Pit	Stone, Crushed/Broken	Surface	Producer	MRDS
Lee Quarry	Stone		Producer	MRDS
Leitner Claim	Chromium		Producer	MRDS
Lime Mountain Quarry	Limestone, General	Surface	Producer	MRDS
Little Bonanza Mine	Mercury		Producer	MRDS
Lucky Strike Mine	Chromium		Producer	MRDS
Mahoney	Mercury		Producer	MRDS
Middlecrest Ranch Deposit	Chromium		Producer	MRDS
Miller Pit	Sand and Gravel, Construction	Surface	Producer	MRDS
Miller Sand Pit	Sand and Gravel, Construction	Surface	Producer	MRDS
Miller Well #2 Mine	Gypsum-Anhydrite	Surface	Producer	MRDS
Millhollin Pit	Stone, Crushed/Broken	Surface	Producer	MRDS
Morro Rock Quarry	Stone, Crushed/Broken	Surface	Producer	MRDS
Mountain Springs Quarry	Stone, Crushed/Broken	Surface	Producer	MRDS
Munari Salinas River Pit	Sand and Gravel, Construction	Surface	Producer	MRDS
Muscio Prospect	Manganese		Producer	MRDS
Navajo Creek Pit	Sand and Gravel, Construction	Surface	Producer	MRDS
New London Mine	Chromium		Producer	MRDS
Norcross Mine	Chromium		Producer	MRDS
North River Road Pit	Sand and Gravel, Construction	Surface	Producer	MRDS
O'Connor Ranch Deposits	Manganese		Producer	MRDS
Oceano Sand Pit	Sand and Gravel, Construction	Surface	Producer	MRDS
Oceano Sand Pit	Stone, Crushed/Broken	Surface	Producer	MRDS
Ormond Road Pit	Sand and Gravel, Construction	Surface	Producer	MRDS
Owen Group	Uranium		Producer	MRDS
Owen-Mitchell-Hillbilly	Uranium		Producer	MRDS
Parker Red Rock Pit	Stone, Crushed/Broken	Surface	Producer	MRDS
Patchett Pit	Sand and Gravel, Construction	Surface	Producer	MRDS
Pereira Group Claims	Chromium		Producer	MRDS
Pick & Shovel Mine	Chromium		Producer	MRDS
Pine Mountain Claims	Chromium		Producer	MRDS
Polar Star Mine	Mercury	Underground	Producer	MRDS
Porter Pit	Sand and Gravel, Construction	Surface	Producer	MRDS
Queen Bee Mine	Gold		Producer	MRDS
Rancho San Simeon Pit	Stone, Crushed/Broken	Surface	Producer	MRDS
Red Rock Pit	Stone, Crushed/Broken	Surface	Producer	MRDS
Rocky Canyon Quarry	Stone, Crushed/Broken	Surface	Producer	MRDS
Rodrigues Pit	Stone	Surface	Producer	MRDS
San Jose Valley Mine	Mercury		Producer	MRDS
San Luis Brick Works, Inc.	Clay	Surface	Producer	MRDS
San Luis Obispo	Mercury		Producer	MRDS
Santa Maria River Pit	Sand and Gravel, Construction	Surface	Producer	MRDS
Santa Maria River Pit	Sand and Gravel, Construction	Surface	Producer	MRDS
Santa Maria River Pit	Sand and Gravel, Construction	Surface	Producer	MRDS
Santa Rita Stone Quarry	Stone, Crushed/Broken	Surface	Producer	MRDS
Single Jack Mine	Chromium		Producer	MRDS
Slash Bar G Ranch Pit	Sand and Gravel, Construction	Surface	Producer	MRDS
Staneuche Mine	Manganese		Producer	MRDS
Still Ranch Property	Gold		Producer	MRDS
Sunshine Claim	Chromium		Producer	MRDS
Sycamore Road Pit	Sand and Gravel, Construction	Surface	Producer	MRDS
Thompson Deposit	Manganese		Producer	MRDS
Tiber Canyon Sand Pit	Sand and Gravel, Construction	Surface	Producer	MRDS
Trinidad Mine	Chromium		Producer	MRDS
Welch Mine	Manganese		Producer	MRDS
Whale Rock Pit	Stone, Crushed/Broken	Surface	Producer	MRDS
Wolforth Quarry #1	Gypsum-Anhydrite	Surface	Producer	MRDS
Young Deposit	Manganese		Producer	MRDS
A-34 Prospect	Gold	Underground	Prospect	MRDS
Alano Creek Deposits	Gypsum-Anhydrite	Surface	Occurrence	MRDS
Alfred H. Ruedy Chrome	Chromium	Surface	Prospect	MRDS
Almaden Deposit	Limestone, General	Surface	Occurrence	MRDS
Alpha Claim	Copper	Surface	Prospect	MRDS
American Canyon Area	Gold	Placer	Prospect	MRDS
Antelope Mud Company	Clay	Surface	Past Producer	MRDS
Arroyo Grande Creek Deposit	Gypsum-Anhydrite	Surface	Occurrence	MRDS
B.e. Prospect	Uranium	Surface	Occurrence	MRDS
Barbara			Occurrence	MRDS
Barbara Claim	Copper	Surface	Prospect	MRDS
Barbara Jane Prospect	Uranium	Surface	Occurrence	MRDS
Barneberg Mine		Surface-Underground	Past Producer	MRDS
Beartrap Creek Area	Gold	Placer	Prospect	MRDS
Bee Tee Prospect	Uranium	Surface	Occurrence	MRDS
Big Bend Claim	Copper	Surface	Prospect	MRDS
Bishop'Ss Peak Quarry	Stone, Crushed/Broken	Surface	Past Producer	MRDS
Black Mountain Prospect	Manganese		Occurrence	MRDS
Black Mountain Prospect		Surface	Prospect	MRDS
Black Widow	Uranium	Surface	Prospect	MRDS
Bluebird Mine		Surface-Underground	Past Producer	MRDS
Bonanza Group			Occurrence	MRDS
Bonanza Group	Copper	Surface	Prospect	MRDS
Borrow Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Borrow Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Borrow Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Borrow Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Borrow Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Buckeye	Mercury		Past Producer	MRDS
Buckeye Mine	Mercury	Underground	Prospect	MRDS
Buena Vista	Mercury	Surface-Underground	Plant	MRDS
Caen Quarry	Stone, Dimension	Surface	Past Producer	MRDS
Caen Quarry	Stone, Crushed/Broken	Surface	Past Producer	MRDS
Cambria	Mercury		Past Producer	MRDS
Cambria Mine	Mercury	Surface-Underground	Past Producer	MRDS
Capitola Mine	Mercury	Underground	Prospect	MRDS
Captain Claim	Chromium	Surface	Prospect	MRDS
Carrisa Mine	Gypsum-Anhydrite	Surface-Underground	Past Producer	MRDS
Carrizo Plain Deposits	Gypsum-Anhydrite	Surface	Past Producer	MRDS
Castro Mine	Chromium		Past Producer	MRDS
Castro Mine	Chromium	Surface	Past Producer	MRDS
Castro No. 2 Claim	Chromium	Surface	Prospect	MRDS
Central Claims	Chromium	Surface-Underground	Prospect	MRDS
Central Claims, Seeley Group	Chromium		Past Producer	MRDS
Chorro Mine	Chromium	Surface-Underground	Past Producer	MRDS
Chromic Acid No. 1 Claim	Chromium		Occurrence	MRDS
Chromic Acid No. 1 Claim	Chromium	Surface-Underground	Prospect	MRDS
Chromic Acid No. 2	Chromium	Surface	Prospect	MRDS
Chromic Acid No. 2 Claim	Chromium		Past Producer	MRDS
Cienaga Mine	Chromium	Surface-Underground	Prospect	MRDS
Clyde's Saylor Prospect	Uranium	Surface	Occurrence	MRDS
Colonel Claim	Chromium	Surface-Underground	Past Producer	MRDS
Colorado Mine	Chromium		Past Producer	MRDS
Colorado Mine	Chromium	Surface	Past Producer	MRDS
Crown Point Claim	Chromium	Surface	Prospect	MRDS
Crown Point Claim, Seeley Group	Chromium		Past Producer	MRDS
Cypress Chrome Prospect	Chromium	Surface	Prospect	MRDS
Cypress Mountain			Occurrence	MRDS
Cypress Mountain Group	Mercury	Underground	Prospect	MRDS
Cypress Prospect, Pick and Shovel Group	Chromium		Occurrence	MRDS
Deer Trail	Mercury		Past Producer	MRDS
Deer Trail Mine	Mercury	Underground	Past Producer	MRDS
Deposit	Barium-Barite	Surface	Occurrence	MRDS
Doty	Mercury		Past Producer	MRDS
Doty Mine	Mercury	Underground	Prospect	MRDS
Dougherty Quarry	Stone, Crushed/Broken	Surface	Past Producer	MRDS
Dubost Deposit	Limestone, General	Surface	Prospect	MRDS
Eagle Prospect	Chromium	Surface-Underground	Prospect	MRDS
Egenes Deposit			Occurrence	MRDS
Egenes Prospect		Surface	Occurrence	MRDS
El Divisadero Mine	Chromium	Surface-Underground	Past Producer	MRDS
El Salto Mine	Chromium	Surface	Past Producer	MRDS
Elizabeth and Winona Group	Mercury	Surface	Unknown	MRDS
Estrella Mine	Chromium		Past Producer	MRDS
Estrella Mine	Chromium	Underground	Past Producer	MRDS
Estrella Sand Pit	Sand, Industrial NEC	Surface	Intermittent	MSHA
Eucalyptus No. 1 Claim	Chromium	Underground	Prospect	MRDS
Eucalyptus No. 2	Chromium	Surface-Underground	Past Producer	MRDS
Eucalyptus No. 2 Deposit	Chromium		Occurrence	MRDS
Eureka Claim	Chromium		Occurrence	MRDS
Eureka Claim	Chromium	Surface	Prospect	MRDS
Evans Manganese Prospects			Occurrence	MRDS
Evans Prospects		Surface	Prospect	MRDS
Evans Ranch Deposit	Chromium	Surface	Occurrence	MRDS
Ezra Carpenter Deposit	Marble, Dimension	Surface	Occurrence	MRDS
F Prospect	Copper	Surface	Prospect	MRDS
Ferrell Deposit	Diatomite	Surface	Occurrence	MRDS
Fine Enterprises	Mercury	Underground	Prospect	MRDS
First Chance Mine	Copper		Prospect	MRDS
First Chance Mine	Copper	Underground	Prospect	MRDS
Fitzhugh Ranch	Mercury		Past Producer	MRDS
Fitzhugh Ranch Deposits	Chromium	Surface-Underground	Prospect	MRDS
Fitzhugh Ranch Mine	Mercury	Surface-Underground	Prospect	MRDS
Florence			Occurrence	MRDS
Florence Claim	Copper	Surface	Prospect	MRDS
Frank Tate Ranch Pit	Stone, Crushed/Broken	Surface	Past Producer	MRDS
Fraser Canyon Prospect	Uranium	Surface	Prospect	MRDS
Frasier Canyon Deposit	Gold	Placer	Prospect	MRDS
Front Door Group	Uranium	Surface	Occurrence	MRDS
Froom Ranch Deposit	Chromium	Surface	Prospect	MRDS
Gemstone Nos. 1, 2, & 3	Mercury	Surface-Underground	Prospect	MRDS
Gloria Placer	Gold	Placer	Prospect	MRDS
Goldtree Vineyard Mine	Chromium	Surface	Past Producer	MRDS
Gravel Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Gravel Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Gravel Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Gravel Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Gravel Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Gravel Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Gravel Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Gravel Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Gravel Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Gravel Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Gravel Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Gravel Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Gravel Pit	Stone, Crushed/Broken	Surface	Past Producer	MRDS
Gravel Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Gravel Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Gravel Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Gravel Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Gravel Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Gravel Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Gravel Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Gravel Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Gravel Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Gravel Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Gravel Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Gravel Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Gravel Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Gravel Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Gravel Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Gravel Pits	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Gravel Pits	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Grey Eagle Mine	Pumice	Surface	Past Producer	MRDS
Guerro			Occurrence	MRDS
Guerro	Copper	Surface	Prospect	MRDS
Guiton Molding Sand	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Hamilton	Mercury		Past Producer	MRDS
Hamilton Mine	Mercury	Underground	Past Producer	MRDS
Hangout Placer	Gold	Placer	Occurrence	MRDS
Hard Face Chromite Mine	Chromium	Surface	Past Producer	MRDS
Haynes Prospects	Gold	Surface	Occurrence	MRDS
Hazzard Group			Occurrence	MRDS
Hazzard Group	Copper		Unknown	MRDS
Hearst Ranch - Marmelejo Creek Deposit	Manganese		Occurrence	MRDS
Hearst Ranch-Marmolejo Cr. Deposit		Surface	Occurrence	MRDS
Hearst Ranch-Red Rock Deposit		Surface-Underground	Past Producer	MRDS
Hill Prospect	Manganese		Occurrence	MRDS
Hill Prospect	Manganese		Unknown	MRDS
Hilltop Claim	Chromium		Occurrence	MRDS
Hilltop Claim	Chromium	Surface	Prospect	MRDS
Hobson			Occurrence	MRDS
Hobson Claims			Occurrence	MRDS
Hobson Claims		Surface	Occurrence	MRDS
Isom Prospect			Occurrence	MRDS
Isom Prospect		Surface	Prospect	MRDS
J Prospect	Uranium	Surface	Occurrence	MRDS
James Wheeler Claims	Chromium	Surface	Prospect	MRDS
Jasper Claim	Chromium		Occurrence	MRDS
Jasper Claim	Chromium	Surface	Unknown	MRDS
Jehovah Jireh Placer	Gold	Placer	Past Producer	MRDS
Jitney Mine	Chromium	Surface-Underground	Prospect	MRDS
Johe Ranch Deposit	Chromium	Surface	Occurrence	MRDS
Johe Ranch Mine		Surface-Underground	Past Producer	MRDS
Johnson Ranch Deposit	Chromium	Surface-Underground	Past Producer	MRDS
Josephine Group	Mercury	Underground	Past Producer	MRDS
Kessler Onyx Deposit	Marble, Dimension	Surface	Past Producer	MRDS
Kester Prospect			Occurrence	MRDS
Kester Prospect	Manganese	Surface	Occurrence	MRDS
Keystone	Mercury		Past Producer	MRDS
Keystone Mine	Mercury	Surface-Underground	Past Producer	MRDS
Kiser Ranch Deposit	Magnesite	Surface	Occurrence	MRDS
Kismet			Occurrence	MRDS
Kismet Group	Mercury		Prospect	MRDS
Klau Mine	Mercury	Surface-Underground	Past Producer	MRDS
La Libertad Mine	Mercury	Surface-Underground	Past Producer	MRDS
La Panza Project	Uranium	Surface	Prospect	MRDS
La Panza Prospect	Uranium	Surface	Occurrence	MRDS
La Primera	Chromium		Past Producer	MRDS
La Primera	Chromium	Surface-Underground	Past Producer	MRDS
Laflor Claim	Chromium		Occurrence	MRDS
Laflor Claim	Chromium		Prospect	MRDS
Lanscioni Prospect			Occurrence	MRDS
Lanscioni Prospect		Surface	Occurrence	MRDS
Last Chance	Gold	Placer	Past Producer	MRDS
Lee Quarry	Stone, Crushed/Broken	Surface	Past Producer	MRDS
Leitner Claim	Chromium	Surface	Past Producer	MRDS
Little Almaden	Mercury		Past Producer	MRDS
Little Almaden Mine	Mercury	Underground	Prospect	MRDS
Little Bend Group			Occurrence	MRDS
Little Bend Group	Copper	Surface	Prospect	MRDS
Little Bonanza	Mercury		Past Producer	MRDS
Little Bonanza Mine	Mercury	Surface-Underground	Past Producer	MRDS
Lopez Canyon Group	Limestone, General	Surface	Prospect	MRDS
Los Berros Canyon	Uranium	Surface	Occurrence	MRDS
Los Osos	Copper		Past Producer	MRDS
Los Osos Mine	Copper		Past Producer	MRDS
Los Osos Mine	Copper	Underground	Past Producer	MRDS
Los Penascos Ranch Deposit	Diatomite	Surface	Occurrence	MRDS
Low Ranch Deposit	Chromium		Past Producer	MRDS
Low Ranch Deposit	Chromium	Surface	Unknown	MRDS
Lowe, Porter, Et Al. Limestone Dep.	Limestone, General	Surface	Occurrence	MRDS
Lowe, Porter, Et Al. Limestone Dep.	Limestone, General	Surface	Occurrence	MRDS
Lucky Jack Group	Copper	Surface	Prospect	MRDS
Lucky Jake Chromite	Chromium	Surface-Underground	Prospect	MRDS
Lucky Strike Mine	Chromium		Past Producer	MRDS
Lucky Strike Mine	Chromium	Surface-Underground	Past Producer	MRDS
Mtn Springs Rd. Pit	Construction Sand and Gravel	Surface	Intermittent	MSHA
Mable G Mine	Chromium	Surface	Past Producer	MRDS
Madrone	Mercury		Past Producer	MRDS
Madrone Mine	Mercury	Surface-Underground	Prospect	MRDS
Manini Property			Occurrence	MRDS
Maninni Nickel Property	Nickel	Surface	Occurrence	MRDS
Marquart			Occurrence	MRDS
Marquart Mine	Antimony	Underground	Prospect	MRDS
Marquart Prospect			Occurrence	MRDS
Marquart Prospect		Surface	Occurrence	MRDS
Mayfield Prospect			Occurrence	MRDS
Mayfield Prospect		Surface	Occurrence	MRDS
McKinney Iron Mines	Iron	Surface	Occurrence	MRDS
Mello Prospects			Occurrence	MRDS
Mello Prospects		Surface	Past Producer	MRDS
Mercury Belle Mine	Mercury	Surface	Prospect	MRDS
Mescal Mine	Chromium		Past Producer	MRDS
Mescal Mine	Chromium	Surface-Underground	Prospect	MRDS
Middlemast Ranch Deposit	Chromium	Surface-Underground	Past Producer	MRDS
Mitchell Property	Uranium	Surface	Occurrence	MRDS
Moonbeam No. 1	Chromium	Surface	Prospect	MRDS
Moonbeam No. 1 Deposit	Chromium		Occurrence	MRDS
Moore Quarry	Stone, Crushed/Broken	Surface	Past Producer	MRDS
Mora Brothers Quarry	Stone	Surface	Past Producer	MRDS
Morgan Limestone Deposit	Limestone, General	Surface	Occurrence	MRDS
Morning Star Placer Mining Co.	Gold		Occurrence	MRDS
Morro Bay Deposit			Occurrence	MRDS
Morro Bay Prospect		Surface-Underground	Prospect	MRDS
Mountain View Deposit	Chromium		Occurrence	MRDS
Mountain View Deposit	Chromium	Underground	Prospect	MRDS
Mt. Butte Chromite Property	Chromium	Surface	Occurrence	MRDS
Muscio Prospect			Past Producer	MRDS
Mutual Chrome Mine	Chromium	Surface	Prospect	MRDS
Navaho Sand Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Navajo Mines	Gold	Placer	Prospect	MRDS
Negrohead	Chromium	Surface	Past Producer	MRDS
New London Mine	Chromium		Past Producer	MRDS
New London Mine		Surface-Underground	Past Producer	MRDS
Newsome Marl Deposit	Calcium	Surface	Occurrence	MRDS
Nicholson Red Rock Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Norcross Mine	Chromium		Past Producer	MRDS
Norcross Mine	Chromium	Surface	Past Producer	MRDS
North Fork Willow Canyon Area	Gold	Placer	Prospect	MRDS
North Star	Mercury		Unknown	MRDS
North Star Claims	Copper	Surface	Prospect	MRDS
North Star and Sunset View			Occurrence	MRDS
O'Connor Ranch Mine		Surface-Underground	Past Producer	MRDS
O.s. Still Ranch Property	Gold	Placer	Past Producer	MRDS
Ocean View	Mercury		Past Producer	MRDS
Ocean View Deposit	Chromium	Surface	Prospect	MRDS
Ocean View Mine	Mercury	Surface-Underground	Prospect	MRDS
Oceanic Mine	Mercury	Surface-Underground	Past Producer	MRDS
Oceano Beach Foundry Sand	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Ore Bag Claim	Chromium		Occurrence	MRDS
Ore Bag Claim	Chromium	Surface-Underground	Prospect	MRDS
Oro Fino	Gold	Placer	Past Producer	MRDS
Outpost Claims	Chromium		Past Producer	MRDS
Outpost Nos. 1 & 2 Claims	Chromium	Surface-Underground	Prospect	MRDS
Owen Group	Uranium	Surface	Past Producer	MRDS
Pacific Coast Coal Company	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Paso Pit and Mill	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Paso Robles Plant	Construction Sand and Gravel	Surface	Intermittent	MSHA
Peppard Ranch Deposit	Chromium	Surface	Occurrence	MRDS
Pereira Claims	Chromium	Surface	Prospect	MRDS
Phelan Prospect			Occurrence	MRDS
Phelan Prospect		Surface	Occurrence	MRDS
Pick and Shovel Mine	Chromium		Past Producer	MRDS
Pick and Shovel Mine	Chromium	Surface-Underground	Past Producer	MRDS
Pine Mountain	Mercury		Past Producer	MRDS
Pine Mountain Claims	Chromium	Surface	Past Producer	MRDS
Pine Mountain Mine	Mercury	Underground	Past Producer	MRDS
Pine Mountain Trail Prospect	Uranium	Surface	Occurrence	MRDS
Pioneer Transit Mix	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Pismo Heights Co.	Diatomite	Surface	Occurrence	MRDS
Polar Star	Mercury		Past Producer	MRDS
Porfumo Canyon Iron Occurrences	Iron	Surface	Occurrence	MRDS
Porta Bros. Ranch Deposit	Chromium	Surface	Occurrence	MRDS
Porta Brothers Ranch Claims	Chromium		Occurrence	MRDS
Prefumo Canyon Prospects			Occurrence	MRDS
Prefumo Canyon Prospects		Surface-Underground	Prospect	MRDS
Prodigal Son			Occurrence	MRDS
Prodigal Son	Copper	Underground	Prospect	MRDS
Prospects	Mercury		Prospect	MRDS
Queen Bee Mine	Gold	Placer	Past Producer	MRDS
Questa Prospect	Chromium		Occurrence	MRDS
Quien Sabe	Mercury		Past Producer	MRDS
Quien Sabe Mine	Mercury	Underground	Prospect	MRDS
Rancho Piedra Blanca Occurrence	Chromium		Occurrence	MRDS
Rancho Santa Rita	Chromium		Past Producer	MRDS
Rawhide Occurrence, Pick and Shovel Group	Chromium		Past Producer	MRDS
Rawhide Prospect	Chromium	Surface	Past Producer	MRDS
Reddin and Venezuela Prospect	Uranium	Surface	Occurrence	MRDS
Refugio			Occurrence	MRDS
Refugio Claim	Copper	Surface	Unknown	MRDS
Ricioli Prospect			Occurrence	MRDS
Ridge	Nickel, Silver, Gold		Occurrence	MRDS
Ridge Claim	Copper	Surface	Prospect	MRDS
Rinconada	Mercury		Past Producer	MRDS
Rinconada Mine	Mercury	Underground	Past Producer	MRDS
Rodilla	Chromium	Surface	Prospect	MRDS
Rodilla Occurrence	Chromium		Occurrence	MRDS
Rogers Ranch Occurrence	Chromium		Occurrence	MRDS
Rogers San Carpojaro Creek Deposits	Chromium		Occurrence	MRDS
Rogers San Carpojaro Creek Deposits	Chromium	Surface	Occurrence	MRDS
Russ Deposit	Chromium		Occurrence	MRDS
Russ Deposit	Chromium		Unknown	MRDS
S. Aumaier Deposit	Dolomite	Surface	Occurrence	MRDS
S. P. Dayton Ranch	Gold	Placer	Unknown	MRDS
San Carpojaro Creek Deposits	Chromium		Occurrence	MRDS
San Carpojaro Creek Deposits	Chromium	Surface	Prospect	MRDS
San Luis Obispo	Mercury		Unknown	MRDS
San Luis Obispo	Nickel	Surface	Occurrence	MRDS
San Luis Obispo Nickel			Occurrence	MRDS
San Luis Range Diatomite	Diatomite	Surface	Past Producer	MRDS
San Ramon	Copper		Past Producer	MRDS
San Ramon Nos. 1, 2, 3, & 4	Copper	Underground	Past Producer	MRDS
San Simeon Creek Deposit	Antimony	Surface-Underground	Past Producer	MRDS
San Simeon Creek Pit & Mill	Sand and Gravel, Construction	Surface	Past Producer	MRDS
San Simeon Creek Pits	Sand and Gravel, Construction	Surface	Past Producer	MRDS
San Simeon Creek Shell Deposits	Calcium	Surface	Occurrence	MRDS
Sand Pit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Sand Pits	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Sandpit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Sandpit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Santa Clara Deposit	Chromium		Occurrence	MRDS
Santa Clara Deposit	Chromium	Underground	Prospect	MRDS
Santa Margarita Platinum Occurrence	Platinum	Surface	Occurrence	MRDS
Santa Margarita Prospects	Uranium	Surface	Prospect	MRDS
Santa Margarita Ranch Shell Dep.	Calcium	Surface	Past Producer	MRDS
Santa Maria Pit and Mill	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Santa Maria Rock Company	Stone, Crushed/Broken	Surface	Past Producer	MRDS
Schlegel North County Sand & Gravel, Inc	Construction Sand and Gravel	Surface	Abandoned	MSHA
Schneider & McCles Claim	Copper	Surface	Prospect	MRDS
Schweider and McCles			Occurrence	MRDS
Seeley Group	Chromium		Past Producer	MRDS
Seeley Group		Surface-Underground	Past Producer	MRDS
Serrano Prospect			Occurrence	MRDS
Serrano Prospect		Surface	Prospect	MRDS
Shandon Deposit	Gypsum-Anhydrite	Surface	Past Producer	MRDS
Silver Swan	Copper		Past Producer	MRDS
Silver Swan	Copper	Underground	Past Producer	MRDS
Single Jack Mine	Chromium	Underground	Past Producer	MRDS
Smith Sand Pit	Construction Sand and Gravel	Surface	Abandoned	MSHA
Soda Lake Deposit	Sodium	Surface	Past Producer	MRDS
Sousa Ranch Deposit	Chromium	Surface	Past Producer	MRDS
Southview Prospect	Mercury	Surface-Underground	Prospect	MRDS
Spring Creek Chrome	Chromium	Surface-Underground	Prospect	MRDS
Staneuche Mine		Surface	Past Producer	MRDS
Stanley Mountain Rare Ii Area	Gold	Underground	Prospect	MRDS
Starlight Claim	Chromium	Surface-Underground	Prospect	MRDS
Starlight Occurrence	Chromium		Occurrence	MRDS
Steele Ranch Deposit	Chromium	Surface-Underground	Prospect	MRDS
Steele Ranch Magnesite	Magnesite	Surface	Occurrence	MRDS
Sunrise No. 1	Chromium	Surface	Prospect	MRDS
Sunrise No. 3	Chromium	Surface-Underground	Prospect	MRDS
Sunrise Nos. 1 and 2 Deposits	Chromium		Occurrence	MRDS
Sunset View Mine	Mercury		Unknown	MRDS
Sunshine Claims	Chromium	Surface-Underground	Prospect	MRDS
Surprise Placer	Gold	Surface-Underground	Prospect	MRDS
Sweetwater Chromite Mine	Chromium	Surface-Underground	Past Producer	MRDS
Sweetwater Mine	Chromium		Past Producer	MRDS
Take A Chance Group	Copper	Surface	Unknown	MRDS
Tamney			Occurrence	MRDS
Tassajara Group	Limestone, General	Surface	Prospect	MRDS
Templeton Pit and Mill	Sand and Gravel, Construction	Surface	Past Producer	MRDS
The Incello Company	Diatomite	Surface	Occurrence	MRDS
Tip Top	Chromium	Surface-Underground	Prospect	MRDS
Tip Top Deposit, Sweetwater-Norcross Group	Chromium		Past Producer	MRDS
Tobacco Creek Prospect			Occurrence	MRDS
Tobacco Creek Prospect		Surface	Occurrence	MRDS
Trinidad Mine	Chromium		Past Producer	MRDS
Trinidad Mine	Chromium	Underground	Past Producer	MRDS
Unknown	Chromium		Occurrence	MRDS
Unnamed Deposit	Sand and Gravel, Construction	Surface	Past Producer	MRDS
Unnamed Deposit	Sand and Gravel, Construction	Surface	Prospect	MRDS
Unnamed Deposit	Sand and Gravel, Construction	Surface	Prospect	MRDS
Unnamed Diatomite Deposit	Diatomite	Surface	Occurrence	MRDS
Unnamed Diatomite Deposit	Diatomite	Surface	Occurrence	MRDS
Unnamed Limestone Deposit	Limestone, General	Surface	Occurrence	MRDS
Unnamed Limestone Deposit	Limestone, General	Surface	Occurrence	MRDS
Unnamed Limestone Deposit	Limestone, General	Surface	Occurrence	MRDS
Unnamed Location	Gypsum-Anhydrite		Occurrence	MRDS
Unnamed Manganese Occurrence	Manganese	Surface	Occurrence	MRDS
Unnamed Manganese Occurrence	Manganese	Surface	Occurrence	MRDS